Archaic word for the dim light of early evening or dusk. In modern Japanese, 夕暮れ (ゆうぐれ) or たそがれ are more common.
In old waka poems, 薄暮れ is sometimes composed about.
Compound of 薄 (usu, 'faint') + 暮れ (kure, 'nightfall'). The exact historical derivation is uncertain, but the spelling is conventionally associated with dim evening light.